SUPPORT US. If is important to you, click here to donate to our Fall 2019 fundraiser!
Log InRegister
Home PageAbout MindatThe Mindat ManualHistory of MindatCopyright StatusWho We AreContact UsAdvertise on Mindat
Donate to MindatCorporate SponsorshipSponsor a PageSponsored PagesMindat AdvertisersAdvertise on Mindat
Learning CenterWhat is a mineral?The most common minerals on earthInformation for EducatorsMindat ArticlesThe ElementsBooks & Magazines
Minerals by PropertiesMinerals by ChemistryAdvanced Locality SearchRandom MineralRandom LocalitySearch by minIDLocalities Near MeSearch ArticlesSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportCoordinate Completion ReportAdd Glossary Item
Mining CompaniesStatisticsUsersMineral MuseumsMineral Shows & EventsThe Mindat DirectoryDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day GalleryMineral Photography

Afterthought Mine, Ingot, East Shasta Copper - Zinc District, Klamath Mts, Shasta Co., California, USA

This page is currently not sponsored. Click here to sponsor this page.
A former Zn-Cu-Ag-Au-Pb mine located in secs. 10, 11 & 15, T33N, R2W, MDM, 0.7 km (2,300 feet) NNW of Ingot and 24 miles E of Redding. Discovered in 1862. First production was 1873. Produced from 1905-1952. Closed in 1952. Owned by the Coronado Copper & Zinc Co. MRDS database accuracy for this location is not stated.

Mineralization is a massive sulphide body hosted in the Bully Hill Rhyolite (Deposit model: Model code 184; USGS model code 28a; Massive sulfide, kuroko, Mark3 model number: 93). The ore body is lenticular in form, strikes NW and dips steeply NE at a length of 121.92 meters. Ore emplacement controls included an intersection between rhyolite - metasedimentary contact and a series of Steeply-dipping strike faults.

The host rock is probably a rhyolite porphyry. Altered rocks contain significant quantities of albite, silica, hydrous mica, calcite and pyrite. Sulphide ore bodies replace sheared host rocks at the contact. 16 ore bodies composed of massive and banded sulphides.

Alteration is local and consists of slicification, pyritization, sericitization, carbonatization, and albitization.

Workings included underground openings with an overall depth of 222.2 meters and a length of 886.97 meters. The overall length of 17,200 feet includes drifts. crosscuts and stopes in addition to 2,200 feet of shafts. raises and winzes.

Production data are found in: Lydon P. A., and O'Brien, J. C. (1972).

Production statistics (1905-1952): ^3.23% Cu, 16.15% Zn, 2.17% Pb, 5.55 o/ton Ag, .03 oz/ton Au.

Mineral List

19 entries listed. 18 valid minerals.

The above list contains all mineral locality references listed on This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.


Hanks, Henry Garber (1884), Fourth report of the State Mineralogist: California Mining Bureau. Report 4, 410 pp. (includes catalog of minerals of California pp. 63-410), and miscellaneous observations on mineral products): 260.

Aubury, Lewis E. (1902), The copper resources of California: California Mining Bureau Bulletin 23: 65.

Diller, J.S. (1906), Description of the Redding quadrangle: USGS Geol. Atlas, Redding folio (No. 138): 12.

Boyle, A.C. Jr. (1914), The geology and ore deposits of the Bully Hill mining district, California: A.I.M.E. Bulletin 85: 57-105; A.I.M.E. Transactions: 48: 67-117 (1915): 98.

Laizure, Clyde McK (1921), Redding field division: California Mining Bureau. Report 17: 528.

Tucker, W. Burling (1924b), Copper resources of Shasta County: California Mining Bureau. Report 20: 426, 427, 445.

Averill, Charles V. (1939), Mineral resources of Shasta County: California Division of Mines Report 35: 127.

Rocks & Minerals (1947): 22: 439.

Albers, J.P. (1953), Geology and ore deposits of the Afterthought mine, Shasta County, California: California Division Mines & Geology Special Report 29: 17.

Stinson, M. C. (1957), California Journal of Mines and Geology, (Report 53): 53: 684.

Albers, John P. & Jacques F. Robertson (1961), Geology and ore deposits of East Shasta copper-zinc district, Shasta County, California, USGS PP 338: 70, 71.

Murdoch, Joseph & Robert W. Webb (1966), Minerals of California, Centennial Volume (1866-1966): California Division Mines & Geology Bulletin 189: 111-112, 130, 134, 340, 361.

Clark, Wm. B. (1970a) Gold districts of California: California Division Mines & Geology Bulletin 193.

Lydon, Philip Andrew and O’Brien, J.C. (1974) Mines and mineral resources of Shasta County, California. California Division of Mines and Geology County Report 6, 154 pp.: 29, 31-33, 33-39, 104.

Pemberton, H. Earl (1983), Minerals of California; Van Nostrand Reinholt Press: 48, 92, 95, 98, 100, 135, 136, 228.

Economic Geology (1988): 83: 588-605.

USGS (2005), Mineral Resources Data System (MRDS): U.S. Geological Survey, Reston, Virginia, loc. file ID #10077520.

Mosier, D.L., Berger, V.I., and Singer, D.A. (2009), Volcanogenic massive sulfide deposits of the world; database and grade and tonnage models: U.S. Geological Survey Open-File Report 2009-1034 [].

Mineral and/or Locality is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization. Public Relations by Blytheweigh.
Copyright © and the Hudson Institute of Mineralogy 1993-2019, except where stated. Most political location boundaries are © OpenStreetMap contributors. relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: December 11, 2019 11:29:57 Page generated: January 11, 2015 22:33:22
Go to top of page